Commercial blasting explosive



Patented Oct." 350, 1928.

UNITED STATES PATENT OFFICE.

RALPH AUSTIN LONG, or TAMAQUA, rENNsYLvAnrA, AssIsNon 'ro ATLAS rowmmcomr nY, or WILMINGTON, DELAWARE, A CORPORATION or nEnAwAnE.

COMMERCIAL BLASTING EXPLOSIVE.

No Drawing.

This invention relates more particularly to commercial blastingexplosives of varying strengths, containing from about 11% to about 47%ammonium nitrate.

Ammonium nitratehas been used'for years as a substitute fornitroglycerine in commercial dynamite. It has the advantage of beingcheaper than nitroglycerine and produoing explosives safer to handle andless easily ignited. One drawback to ammonium nitrate is that itcontributes very little to the propagation sensitiveness of explosivesand therefore must be used in conjunction with a sensitizer consistingusually of an explosive organic nitrate or nitrates or some explosivenitro aromatic compound or com-' pounds or both.

Under normal conditions these sensitizing explosives are much morecostly, strength for strength, than ammonium nitrate. Alsonitroglycerine or a mixture of nitroglycerine'with nitrated polymerizedglycerine, which are the most common explosive organic nitrates used assensitizers, have the disadvantage of causing severe headaches to thosehandlin them, are extremely sensitive to shock, and become uitedangerous to handle when frozen. hese undesirable properities areinherent in the explosives containing them to an extent depending, in agereral way, on the quantity used, although not necessarily in directproportion to that quantity. In explosives containing, for example, 50%

or 40% nitroglycerine or some similar ex plosive organic nitrate, itwould be a difiicult matter to determine much difference between them inregard to such properties. But as the nitroglycerine content is furtherreduced 'these undesirable properties become less noticeable, andespecially so during successive reductions below about 12%. There is alimit however, below which any further reduction in the nitroglycerinecontent seriously interferes with the propagation sensitiveness.

By extensive thought and a vast number of tests on various combinationsof the explosive ingredients, I have succeeded in obtaining satisfactorypropagation sensitiveness although reducing the quantity of sensitizingcompound or compounds to a great Application filed May 13, 1925. SerialNo. 30,087.

ered practicable explosives containing from about 11% to about 47%ammonium nitrate. Ivhave therefore obtained greater economy inmanufacture and in the use of ingredients, while at the same time, Ihave but not in an amount .sufiicient to interfere with the otherdesirable features of my explosive such as its great economy, safety,and. reduced tendency to cause headaches. Explosive nitroaromaticcompounds may be used in a limited amount as an additional sensitizerand to lower the freezing point. Inorganic nitrates may also be used asa filler and to provide the desired amountof oxygen, together withvarious well known ingredientsof a non-explosive but combustible naturesuch as ground wood, sulphur, etc. Briefly, my explosive contains a881181- tizer which is never in excess of 12 per cent and which consistsof from four andonehalf to eight and one-half per cent, (4%% to 8 5%) ofan explosive liquid orgamc nitrate or a mixture of explosive liquid or-'ganic nitrates and from zero" to seven andone-half per cent, (0 to 7ofan explosive nitroaromatic compound or compounds such astrinitrotoluene for. example,

together with from about eleven to" about forty-seven per cent, (11% to47%) am monium nitrate, depending on the strength desired, together witha non-explosive inorganic nitrate or nitrates to act as a filler andsupply a desired amount of oxygen. In addition to these, variousquantities of nonexplosive combustible materials may be added for thepurpose of mampulatmg the,

density or oxygen balance without departing from the spirit of myinvention. Where the term nitrate is used in the accompanying claims, itis to be understood to includ mixtures of nitrates.

The following are typical formalae of my explosives:

Although I have used, in these examples, amixture of nitroglycerine andtetranitrodiglycerine as the llquid explosive organic nitrate, I mayalso use nitroglycerine (glycerine trinitrate) alone, or mixtures ofglycerine trinitrate with other liquid explosive organic nitrates, suchas the glycol dinitrates, chlorhydrindinitrate, and suitable nitratedcarbohydrates, or I may use explosive liquid organic nitrates exclusiveof glycerine trinitrate.

Having described my invention, what I claim is:

1. A blasting explosive ofthe character described, comprisingnitro-glycerine upvto 8%, ammonium nitrate, trinitrotoluene and anon-explosive combustible, the nitroglycerine and the trinitrotoluenecomplementally constituting a sensitizer not in excess of 12 per cent ofthe Whole, and in which the nitroglycerine is in excess of thetrinitrotoluene.

2. A blasting explosive of the character described, comprising thefollowing ingredients combined in substantially the proportions. stated,viz: ammonium nitrate up to ,47 per cent; nitroglycerine not to exceed 8per cent; sodium nitrate from 33 to 47 .5 per cent; trinitrotoluene 2per cent, and a nonexplosive combustible.

In testimony whereof he affixes his signe ture.

RALPH AUSTIN LONG.

